JAKARTA, Indonesia - Six people lost their lives while more than 200 suffered injuries after mobs clashed with security forces and set fire to a police dormitory and vehicles in the Indonesian capital following the release of official election results a day earlier, authorities said on Wednesday.

"Six people have died so far. Two at Tarakan Hospital and then at Pelni, Budi Kemulyaan, Cipto Mangunkusumo and RSAL Mintoharjo hospitals," The Jakarta Post quoted Jakarta's Governor Anies Baswedan as saying.

"In total, six people have died and 200 sustained injuries as of 9:00am," he added.

Protests by supporters of losing presidential candidate Prabowo Subianto turned violent late on Tuesday and continued through the night.

Baswedan said he had gone to Tarakan Hospital in Central Jakarta earlier in the morning to check on the injured protesters.

"Tarakan Hospital received the largest number of patients as of this morning. Around 80 injured protesters were brought in this morning. Meanwhile, around 70 injured protesters were admitted to Pelni Hospital in West Jakarta," he said.

Amid violence, the governor further called on the protesters to maintain public order and safety to prevent more deaths and injuries.

"Please protest in a peaceful and orderly manner. I also urge law enforcement personnel to practice restraint to avoid any unwanted conflicts with the protesters," he said.

Jakarta has been on edge in recent days ahead of the official announcement of the April presidential election results, which on Tuesday confirmed that incumbent President Joko Widodo had won a second term, with 55.5 per cent of the votes.

His opponent, ex-special forces commander Subianto had refused to accept the results, alleging that the poll since April 17 was marred by massive and systematic fraud.

"We reject the final presidential vote tally by the KPU. And we'll take all available legal avenues supported by the Constitution," Prabowo was quoted as saying on Tuesday at his home in South Jakarta.

The opposition said on Tuesday they would contest the results in court, a repeat move of Prabowo's unsuccessful bid for president in 2014.

Meanwhile, the General Elections Commission (KPU) of Indonesia said the losing candidate pair had until Friday to file a lawsuit to contest the results, within three days of the official announcement of the vote tally.

If no legal challenge is filed, the KPU will officially name Jokowi and Ma'ruf the president- and vice president-elect for the 2019-2024 period on Friday, KPU head Arief Budiman told reporters on Wednesday. (ANI)